Why a Telescope does not need an Eyepiece

Without telescopes, astronomy would not be as popular as today: observing celestial objects through these instruments is a way of being aware of the immensity and the beauty our starry sky features. Astronomical observation enables us to experience directly the marvelous pictures of galaxies, nebulae, star clusters that we see on the Internet or in astronomy books.

But, have you ever looked at the Andromeda Galaxy through the eyepiece of a telescope? Were you surprised to see only a blurred spot, diffuse and without any colors?It’s a shame, you are told that this object is identical to the Hubble’s picture you found on the Internet!

Today, it is obvious that astronomical observation should be redesigned, modernized and enhanced. Professional astronomers were moreover the first ones to observe the sky using digital images displayed on their computer screens. In a similar way, the French start-up Vaonis offers an original feature which updates stargazing: “photobservation,” which consists of observing objects of our sky with an eyepiece-free telescope equipped with a very high definition camera, sending color images of the object you are looking at in real time to your smartphone or tablet!

If you are among those who are not convinced that the future of astronomical observation is in the replacement of telescope eyepieces by high-performance cameras transferring data directly to our connected devices, you should keep reading this article. It might change your point of view.

Observation through an eyepiece: the biggest disappointment of astronomy!

Contrary to the expectations of most people, looking through a telescope’s eyepiece does not mean observing images as sharp, as bright and as colorful as the ones we often see on Internet or in scientific magazines.

The overall image quality does not depend solely on the optical quality of the telescope, but rather on the capabilities of our eyes. Although our eyes are extremely powerful tools that no camera could match, when night falls, that is no longer the case!

The weaknesses of the human eye in astronomy: anatomy reminder

First of all, our eyes require a minimum amount of time to adjust to darkness. Between 10 and 15 minutes are needed in order to detect the slight contrast of a nebula or galaxy through a telescope or even of the Milky Way observed by the naked eye.
Obviously, our eye sensitivity is limited and does not permit us to observe objects of the starry sky at their best.

Composition of human eye

The human eye contains two kinds of photodetectors which are spread out on the surface of the retina: cones and rods. These photo-receivers are responsible for our sight and our ability to detect different colors. Cones are sensitive to colors and are divided into 3 types: red, green and blue. They are constantly used for our daylight vision, but when the luminosity plummets, the rodstake their place. Rods are far more numerous than the cones but are insensitive to color!

On one hand, it is thanks to the rods that we have night vision at all, and on the other hand, it is because of them that our night vision is only in shades of black and white!

As a consequence, we will never be able to observing the colors of galaxies and nebulae without a huge amount of light to make their shapes and borders stand out. This applies both to telescope eyepiece observation and to naked eye observation.

The drawbacks of classical observation: one observer at a time

Even without taking into account the physical limits of our eyes, telescope observation has not always been as simple as one might think. Here is a list of difficulties encountered when observing through the eyepiece of a telescope:

Lonely observation because only one person at a time can observe through the instrument

The eye should not touch the eyepiece in order to keep the telescope stable

The focus is different for every observer, and the telescope shakes while adjusting it

The observation position is often uncomfortable: you must bend, crouch or even climb up to reach the eyepiece!

A screen: observing + photographing = “photobserving”

Image comparison between of the Orion Nebula as seen with the eye through the eyepiece of a telescope (left, simulation) and an image obtained with a telescope with an embedded camera like Stellina (right)

In the end, eyepiece observation is not the best way to appreciate the beauties of the universe. In addition to being uncomfortable, traditional observation is limited by the capacity of our eyes to differentiate among the low luminosity stars and other celestial objects.

The primary purpose of astronomical observation is to observe objects of the sky with the highest quality possible. Since modifying the human eye remains impossible, the typical solution for improvement is to purchase bigger telescopes, which leads to spending more money. Even with larger telescopes, the result sill does not match our expectations.

Given this frustrating limiting factor of our eyes, a question can arises: since nowadays we have technology powerful enough to exceed the performance of our eyes at the night, wouldn’t it make more sense to remove the eyepiece and instead embed a CCD sensor?

Observing the colors of the Universe, at last!

Indeed, not only does a photo sensor reveal the true colors of nebulae and galaxies but also enables us to detect objects which were totally invisible through a telescope eyepiece!

The list of accessible sky objects thus becomes richer and the satisfaction of these images is even greater, because they reveal much more detail.

Real-time images on your smartphone

No need to adjust your night vision and to try to guess which astronomical object you are looking at. The captured photograph is directly shown on your tablet’s or smartphone’s screen, through WiFi.

Importantly, a Stellina telescope does not simply display an instantaneous grayish view of an object; rather, it uses the process of live-Stacking, which consists basically of taking a series of pictures and superimposing them one by one. This technical process derives from practices by professional astronomers, and enables Stellina to make the celestial body stand out while the clock is ticking, by light amplification. The longer you keep the telescope pointed at an object, the brighter and the more visible it will be.

The mobile app provided with Stellina performs the entire image processing and automaticallychooses the suitable image processing for each object. This permits you to avoid the complicated and unintuitive field of astronomical image processing.

A screen for sharing your experience and having a collective observation

Using the screen of a smartphone to replace the telescope eyepiece is especially appreciated when you wish to move freely about your telescope without having to come back and forth to it every minute. With this system, it is now possible to invite family or friends to observe your images simultaneously keeping your seat on your patio or even in your living room!
Your tablet serves as a support to look at your pictures and also as an interactive link to share your experience on every social network.

Sharing your astrophotographical work will never be as simple and effective as with Stellina. Stellina allows each of us to SHARE OUR UNIVERSE!

New future for astronomy

Thanks to an eyepiece-free telescope, you will never need to fuss with focusing the telescope, changing the eyepiece, etc. The telescope will be ready to use within a few seconds.

A telescope like Stellina can help you observe the beauty of our universe at it’s best, and even make your first steps in advanced astronomy: collaborative astronomy. Asteroid occultations with 3D rendering, variable stars monitoring, exoplanet transits wich were previously limited to professional astronomers will now all be accessible to everyone.

Select the Universe which suits you the best with a new generation telescope: Stellina.